|Número de publicación||US4518753 A|
|Tipo de publicación||Concesión|
|Número de solicitud||US 06/485,586|
|Fecha de publicación||21 May 1985|
|Fecha de presentación||15 Abr 1983|
|Fecha de prioridad||26 Abr 1982|
|También publicado como||DE3315016A1|
|Número de publicación||06485586, 485586, US 4518753 A, US 4518753A, US-A-4518753, US4518753 A, US4518753A|
|Inventores||David H. Richards, Malcolm J. Stewart|
|Cesionario original||National Research Development Corporation|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citas de patentes (6), Otras citas (1), Citada por (71), Clasificaciones (18), Eventos legales (4)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
The present invention relates to a process for the anionic polymerisation of conjugated 1,3-dienes in a polar solvent and, in particular, to such a process when initiated by a difunctional initiator.
Highly useful polymeric products can be obtained by polymerising olefinic containing monomers in the presence of an organo-alkali metal initiator and subsequently reacting the resulting polymer, containing an active alkali metal end group or groups, with a reagent which, will either couple the polymer molecules or replace the alkali metal with more stable reactive end groups.
It can be seen that such a polymerisation process will consist essentially of three stages:
(a) Initiation, in which the monomeric material is contacted with a monofunctional or difunctional anionic initiator,
(b) Propagation, in which the monomer is allowed to polymerise to form living polymer chains with negatively charged ends, and
(c) Termination, in which the living polymer chains are treated with suitable reagents, generally to form monofunctionally or difunctionally terminated polymers.
The presence of a reactive terminal group or groups on the ends of the polymer molecules enables substantially more effective cures to take place. In the case of a polymer containing a reactive group on each of its ends (a telechelic polymer) all of the polymer molecule will be tied into the cross-linked structure of the cured material. The well defined structure produced by telechelic polymers in the networks of their cured products is the primary reason for their increased use as precursors in the commercial production of cured rubbery solids.
However, in order to meet the requirements of a modern synthetic rubber it is not enough that the polydiene precursor produces effective cures nor that the cured product has a well defined cross linked structure, it is also important that the cured product possesses good elastomeric properties. In the case of polydienes the elastomeric quality of the cured product is dependent upon the 1,4-content of the polymeric diene. Generally, the higher the 1,4-content of the polymer, the better the elastomeric properties of the cured product. It follows from this that any process chosen for the commercial production of polydienes (in particular telechelic polymers of 1,3-dienes) must lead to a material having a high 1,4-content.
It is well established that high 1,4-monofunctional polydienes an be prepared in inert hydrocarbon solvents by initiating the reaction with a monofunctional initiator such as butyl lithium. As yet it has not been possible to use these conditions in the preparation of telechelic polydienes since difunctional initiators are generally insoluble in non polar solvents such as hydrocarbons.
A possible alternative to the above reaction scheme would be to replace the hydrocarbon by a polar solvent, such as ether or tetrahydrofuran, in which the difunctional initiator is soluble. Unfortunately the effect of such polar solvents on the anionic polymerisation of 1,3-dienes, whether initiated by mono- or difunctional initiators, is already well established, the material produced having a very low 1,4-content (ca.10%) and inferior elastomeric properties after cross linking.
At present, therefore, telechelic polymers of 1,3-dienes are prepared by a free radical process, in which initiation is effected by a functional radical, rather than by an anionic process. An example of this free radical polymerisation is the production of hydroxy terminated polybutadiene (HTPB) by the action of hydrogen peroxide and ferrous iron on butadiene. Although the materials prepared by this free radical technique possess the required high 1,4-structure (ca.80%), they have also been found to suffer from two major disadvantages. These are that the materials are not uniquely difunctional and that they have a broad molecular weight distribution.
In principal both of these disadvantages could be overcome by preparing the monofunctional or telechelic polymers by an anionic polymerisation in a polar solvent. As we have seen however the use of these conditions has previously been inhibited by the very low 1,4-content of the material produced.
It is the main object of the present invention to provide a process for the anionic polymerisation of a conjugated 1,3-diene in a polar solvent which produces a polymeric material having a narrow molecular weight distribution, an enhanced 1,4-content and, in the case of telechelic polymers, an enhanced difunctional specificity. Other objects and advantages of the present invention will become apparent from the following description thereof.
According to the present invention there is provided a process for the anionic polymerisation of a conjugated 1,3-diene in a polar solvent comprising contacting the conjugated 1,3-diene with an organo alkali or alkaline earth metal initiator in the presence of a sterically hindered Lewis acid.
The Lewis acid of the present invention must be sterically hindered. In other words it will preferably be chosen from those organometallic acids that are inaccessible to attack by the electron rich propagating anion, that is those acids whose rate of reaction with the propagating anion, to form a stable Lewis acid salt, ranges from very slow (relative to the rate of propagation) to zero. Preferably the Lewis acid will be a substituted triaryl derivative of a Group III element although in certain cases, where the aryl derivative itself is large the Lewis acid may be an unsubstituted triaryl derivative of a Group III element. Preferably the Group III element is either boron or aluminium, with boron being particularly preferred. Examples of Lewis acids suitable for use in the present process are trimesityl boron (tri(2,4,6-trimethylphenyl)boron) and tri(2,6-dimethylphenyl)boron. An example of a Lewis acid that is unsuitable for use, its metal atom being insufficiently sterically hindered, is triphenyl boron. In this latter case the addition of the Lewis acid (triphenyl boron) almost immediately terminates the polymerisation of the diene with the formation of the stable polydiene triphenyl boron adduct.
The conjugated 1,3-dienes of the present invention will preferably contain from 4 to 12, especially from 4 to 8, carbon atoms per molecle. Examples of these compounds include the following: 1,3-butadiene; isoprene; 2,3-dimethyl-1,3-butadiene; 1,3-pentadiene; 2-methyl-3-ethyl-1,3-butadiene; 3-methyl-1,3-butadiene; 2-methyl-3-ethyl-1,3-pentadiene; 2-ethyl-1,3-pentadiene; 1,3-hexadiene; 2-methyl-1,3-hexadiene, 1,3-heptadiene; 3-methyl-1,3-heptadiene; 1,3-octadiene; 3-butyl-1,3-octadiene; 3,4-dimethyl-1,3-hexadiene; 3-n-propyl-1,3-pentadiene; 4,5-diethyl-1,3-octadiene; phenyl-1,3-butadiene; 2,3-diethyl-1,3-butadiene; 2,3-di-n-propyl-1,3-butadiene and 2-methyl-3-isopropyl-1,3-butadiene. Among the dialkylbutadienes, it is preferred that the alkyl groups contain from 1 to 3 carbon atoms. Of the above monomers 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene and 1,3-pentadiene are preferred, with 1,3-butadiene being particularly preferred. The conjugated dienes may be polymerised alone, or in admixture with each other to form copolymers or by charging the dienes sequentially to form block copolymers.
The organo alkali or alkaline earth metal initiator may be either a mono- or, which is preferred, a difunctional initiator of anionic polymerisation reactions, depending upon whether a monofunctionally terminated or a telechelic polymer is required. Preferably the initiator is either an alkyl or an aryl salt of either lithium or sodium. Examples of suitable monofunctional initiators are monoalkyl lithium salts such as n-butyl and sec-butyl lithium. Examples of suitable difunctional initiators are aryl or aralkyl sodium compounds such as the disodium tetramer of α-methylstyrene (α4Na2) and the electron transfer reagent sodium naphthalene (NaN) and alkyl lithium compounds such as 1,4-dilithiobutane.
The polar solvent will be an organic solvent that meets the following criteria:
(a) dissolves both monofunctional and difunctional anionic initiators,
(b) acts as a good solvating solvent, and
(c) does not terminate the anionic polymerisation reaction.
Generally the alkyl or cycloalkyl ethers, such as diethyl ether, diisopropyl ether and, especially, tetrahydrofuran, are preferred, although nitrogen containing solvents, such as tetramethyl ethylene diamine, may also be useful.
The present polymerisation process may be initiated either before or after the Lewis acid has been added to the bulk of the conjugated 1,3-diene. For example the polymerization of 1,3-butadiene may be effected in the manner of this invention by this consecutive addition of sodium naphthalene and trimesityl boron to the monomer containing solution. Alternatively the polymerisation may be effected by first splitting the diene into a major and a minor component, then adding trimesityl boron to the major component and sodium naphthalene to the minor component and finally mixing the two components together. It can be seen that in the first case the reaction is initiated before the addition of the Lewis acid, whilst in the second case initiation takes place after the Lewis acid has been added to the bulk of the monomer. Other variations in the manner of initiating the present process will be apparent to those skilled in the art. It should be noted, for the avoidance of doubt, that the phrase "contacting the 1,3-diene with the organo alkali or alkaline earth metal initiator in the presence of a sterically hindered Lewis acid", when used in the present specification, incorporates all such variations in the manner of initiation.
After propagation has ceased, the active centre or centres on the living polymer chains may be terminated, by the addition of suitable reagents which either donate a proton to or functionalise the anionic carbons. Proton donors such as water or alcohol yield terminally non-functional polydienes. Preferably, however, the polymer chains will be terminated by one or, which is particularly preferred, two functional groups. Examples of suitable end groups are:
(a) carboxyl, prepared by adding CO2 to the anionic polymer,
(b) hydroxyl, prepared by adding aldehydes, ketones or alkylene oxides, especially ethylene oxide,
(c) mercapto prepared by adding sulphur, cyclic disulphides or cyclic sulphides such as ethylene or propylene sulphides,
(d) amino and aziridine, prepared by adding aminoaldehydes or polyaziridines such as phenyl-bis(2-methyl-1-aziridinyl)phosphine oxide, and
(e) epoxide, prepared by adding glycidaldehyde or diepoxides.
The present polymerisation reaction is preferably carried out at a temperature in the range between 0° and 100° C., especially between 20° and 80° C. The maximum temperature that may be employed in a given system will depend primarily on the solvent chosen, for example in THF the maximum temperature is 66° C. Generally, temperatures towards the upper end of these ranges are preferred since, in most cases, the 1,4-content of the polydiene increases as the temperature increases.
The amount of initiator added to the reaction mixture will be determined by the structure of the monomer to be polymerised and by the desired molecular weight of the polymer. Typically, for the production of liquid polymers, between about 10 and 50 mmoles, especially 15 and 35 mmoles of initiator is used for each mole of monomeric diene.
By contrast the amount of Lewis acid added to the reaction mixture is determined by the level of 1,4-polymerisation that is required. The present inventors have found that the higher the molar ratio of Lewis acid to initiator the higher the 1,4-content of the polymer produced. Thus, although a molar ratio (Lewis acid to initiator) of about 1 to 1 may be useful for some purposes, a molar ratio of between 2 to 1 and 10 to 1 is generally preferred.
Preferably the terminally reactive polymers produced by the present process are liquids having an average molecular weight in the range of 2000 to 10000, especially 3000 to 7000. If desired however semi-solid and solid polymers having an average molecular weight of 100,000 or above may also be prepared.
The present polymerisation process offers a number of significant advantages over its competitors. First the molecular weight distribution (Mw/Mn) is narrower than that achieved by the analogous free radical process. In the present case the molecular weight distribution is generally about 1.3 or less whilst in the competing process Mw/Mn is generally 1.5 or above. The advantage offered by a polymer with a narrow Mw/Mn is that it produces a cured product with a well defined network and, as a consequence, high strength.
Although the present process produces a polymer with a narrow molecular weight distribution its use is not limited to the production of such polymers. Simply by mixing batches of the present polymers, each batch having a different molecular weight range, a polymeric mixture with a broad molecular weight distribution may be produced. Thus, unlike its competitors, the present process may be employed to produce polymeric materials with either a narrow or a broad molecular weight distribution.
The second advantage offered by the present process is the enhancement of the 1,4-content of a polydiene when such a material is produced in a polar solvent by anionic polymerisation. The degree of enhancement will be determined not only by the choice of the Lewis acid but also by other reaction conditions such as the reaction temperature, the molar ratio of Lewis acid to initiator and the choice of initiator. For example, when the polymerisation of butadiene, initiated by α4 Na2, is conducted in tetrahydrofuran in the absence of a Lewis acid, the 1,4 content of the polymer obtained is about 13%. The addition of trimesityl boron to the above reaction mixture, in a 1 to 1 and 3 to 1 molar ratio of acid to initiator, increases the 1,4 content of the product to, respectively, 25 and 51%.
The third advantage of the present invention is the enhanced difunctional specificity of the telechelic polymers produced therein (compared to those produced by free radical processes). In order to lead to a cured solid with a well defined network (and high strength) a telechelic polymer should consist predominantly of polymer molecules that are only functionalised at their chain ends. This terminal functionalisation minimises the number of free chain ends that are present in the cured product and is primarily responsible for the favourable polymer network structure obtained. It is well established that the free radical polymerisation of conjugated 1,3-dienes in hydrocarbon solvent can often lead to a material that exhibits a significant amount of branching (with a consequent molar functionality of greater than 2). By contrast the present inventors have found that the polymeric materials formed in the present process have virtually no branching (and a consequent molar functionality of close to 2).
A further advantage of the present invention lies in the polarity of the solvent and the type of initiator that may, as a consequence, be used to initiate the reaction. In particular the use of a polar solvent allows electron transfer agents, such as sodium napthalene, and low molecular weight organo alkali metal compounds, such as 1,4-dilithiobutane to be employed as difunctional initiators in the present process. It is a feature of these initiators that they do not significantly affect the properties of the polydiene produced in the polymerisation reaction even if that polydiene is of low molecular weight (less than 5000).
The process of the present invention will now be described by way of example only.
Butadiene (Air Products) was dried by passing the monomer over molecular sieves and collected in a graduated vessel at -78° C. Trimesityl boron (TMB, Alfa) was recrystallised from a benzene/methanol mixture, dried and stored under vacuum until use. Tris(2,6-dimethylphenyl)borane was prepared using the method of Brown etal, JACS, 1957, 79, 2302.
n-Butyl lithium (Aldrich) was supplied and used as a 1.6M solution in hexane.
Naphthalene (BDH, molecular weight determination grade) was used as supplied.
α-Methylstyrene (BDH) was dried over calcium hydride, then redistilled under reduced pressure and the middle fraction collected (bp 26° C. at 1 mm Hg).
Sodium metal (BDH), supplied as pellets under paraffin oil, was washed in 60-80 petroleum ether and pressed into 2 mm diameter wire for use.
Sodium naphthalene (NaN) was prepared by the process of Burgess, MSc. Thesis, Univ of St Andrews, 1976.
The disodium tetramer of α-methylstyrene (α4 Na2) was prepared by the process of Richards etal, Chem Commun, 1967, 414 or J Poly Sci Poly Chem Ed, 1973, 11, 80.
Tetrahydrofuran (BDH), stabilised with 0.1% quinol, was distilled under nitrogen when required after sufficient 0.7M sodium naphthalene solution in THF had been added to yield a permanent green colour.
Reactions were carried out in a nitrogen atmosphere. Conventional quickfit glassware was used which was subjected to the following cleansing procedure:
It was heated to 500° C. overnight in a muffle furnace, cooled to room temperature and then washed in chromic acid, water (twice) and acetone. It was then dried in an oven at 80° C. until required.
Reagents were introduced as solutions by syringe through Subaseal serum caps (Gallenkamp). The syringes had been previously subjected to the cleansing procedure described above.
A 500 ml. round bottomed 3 necked flask equipped with a magnetic follower, serum cap, bubbler for butadiene and a nitrogen inlet/outlet was used as the reaction vessel. Tetrahydrofuran (200 ml.) together with butadiene (10 ml out of 80 ml stored in an attached graduated flask) was introduced to the vessel. Butyl lithium (0.016M) was then injected and the monomer in solution was allowed to polymerise for 5 min. After this time a reference sample was removed from the vessel and terminated by the addition of methanol. A solution of trimesityl boron (0.016M) in THF (10 ml) was then added to the reaction mixture and this was followed by the remaining butadiene. The polymerisation reaction was allowed to proceed at 20° C. for 30 min before being terminated by the addition of methanol.
It was noted that the colour of the solution changed on addition of TMB from the yellow characteristic of the polybutadienyl anion to purple, and that the intensity of this coloration increased as the reaction proceeded.
The sample and reference solutions were then reduced in volume by rotary evaporation and the polymers were precipitated by the addition of ethanol and dried.
The molecular weights and the percentage 1,4-structure of both the sample and the reference were determined by Gel Permeation Chromatography (gpc) in which measurements were carried out on a Dupont Series 870 chromatograph fitted with refractive index and uv detectors. Four styrogel columns (Polymer Laboratories) of porosity 105 Å, 104 Å, 103 Å and 102 Å were used, and the molecular weights were determined from retention times as polystyrene equivalents, and 1H Nuclear Magnetic Resonance (nmr) Spectography in which measurements were carried out on either Varian Associates EM 60 MHz spectrometer or a Jeol PS 100 MHz spectrometer. Polymer samples were also analysed on a Jeol FX 90 φ 90 MHz Fourier Transform multiprobe spectrometer. Results are given in Table 1.
The procedure of Example 1 was repeated except that the reaction was terminated with ethylene oxide rather than methanol. The usual work up procedure produced a hydroxy terminated polybutadiene.
The procedure of Example 1 was repeated except that the reaction was terminated by contacting the living polymer with carbon dioxide. The usual work up procedure produced a carboxy terminated polybutadiene.
The procedure of Example 1 was followed except that the whole sample of butadiene was added to the reaction mixture prior to the addition of trimesityl boron.
The procedure of Example 1 was followed except that the amount of trimesityl boron added was increased to 0.032M.
The 1,4 content of the resultant polymer is given in Table 1.
The procedure of Example 1 was followed except that the amount of trimesityl boron added was increased to 0.048M.
The 1,4-content of the resultant polymer is given in Table 1.
The procedure of Examples 1-3 were followed, to produce hydrogen-, hydroxy- and carboxy-terminated polybutadienes, except that α4 Na2 (0.008M) replaced butyl lithium as the initiator.
The 1,4-content of the resultant hydrogen-terminated polybutadiene is given in Table 1.
The procedures of Examples 5 and 6 were followed except that α4 Na2 (0.008M) replaced butyl lithium as the initiator.
The 1,4-content of the resultant polymers is given in Table 1.
The procedures of Examples 1-3 were followed, to produce hydrogen-, hydroxy- and carboxy-terminated polybutadienes, except that sodium naphthalene (0.008M) replaced butyl lithium as the initiator.
The 1,4-content of the resultant hydrogen terminated polymer is given in Table 1.
The procedures of Examples 5 and 6 were followed except that sodium naphthalene (0.008M) replaced butyl lithium as the initiator.
The 1,4-content of the resultant polymers is given in Table 1.
TABLE 1______________________________________The effect of trimesityl boron on the structure of polybutadieneformed in an anionically initiated polymerisation in THF at 20°C. Molar Ratio of Lewis 1,4-Content ofExample Initiator Acid to Initiator Polybutadiene (%)______________________________________Control Bu Li -- 9 1 Bu Li 1 to 1 20 5 Bu Li 2 to 1 25 6 Bu Li 3 to 1 29Control α4 Na2 -- 13 7 α4 Na2 1 to 1 2510 α4 Na2 2 to 1 4211 α4 Na2 3 to 1 51Control NaN -- 1012 NaN 1 to 1 2915 NaN 2 to 1 3916 NaN 3 to 1 47______________________________________
The procedure of Example 5 was repeated except that the polymerisation was conducted at the following temperatures, -25°, 0° and 45° C., rather than at 20° C.
The 1,4-content of the resultant polymers is given in Table 2.
TABLE 2______________________________________The effect of temperature on the structure of polybutadiene formedin a BuLi initiated polymerisation in THF in the presence oftrimesityl boron (molar ratio TMB to BuLi, 2 to 1) 1,4-Content ofExample Temperature (°C.) Polybutadiene (%)______________________________________17 -25 1318 0 21 5 20 2519 45 32______________________________________
The procedure of Example 1 was followed except that tris(2,6-dimethyl phenyl)boron (0.016M) replaced trimesityl boron as the Lewis acid and the reaction temperature was decreased to -5° C.
The 1,4-content of the resultant polymer is given in Table 3.
The procedure of Example 20 was followed except that the amount of tris(2,6-dimethylphenyl)boron was increased to 0.032M.
The 1,4-content of the resultant polymer is given in Table 3.
The procedures of Examples 20 and 21 were followed except that the reaction temperature was increased to 25° C.
The 1,4-content of the resultant polymer is given in Table 3.
The procedure of Example 20 was followed except that the amount of tris(2,6-dimethylphenyl)boron was increased to 0.048M and the reaction temperature was increased to 25° C.
The 1,4-content of the resultant polymer is given in Table 3.
TABLE 3______________________________________The effect of tris (2,6-dimethyl phenyl) boron on the structureof polybutadiene in an anionically initiated polymerisation in THF. Tempera- Molar Ratio of Lewis 1,4-Content ofExample ture (°C.) Acid to Initiator Polybutadiene (%)______________________________________Control -5 -- 1720 -5 1 to 1 2121 -5 2 to 1 25Control 25 -- 1322 25 1 to 1 2223 25 2 to 1 3324 25 3 to 1 44______________________________________
The procedures of Examples 7 and 10 were followed except that isoprene replaced butadiene as the 1,3-diene and the reaction was conducted at 0° C.
The 1,4-content of the resultant polymer is given in Table 4.
TABLE 4______________________________________The effect of trimesityl boron on the structure of polyisopreneformed in an anionically initiated polymerisation in THF at 0° C. Molar Ratio of Lewis 1,4-Content ofExample Initiator Acid to Initiator Polyisoprene (%)______________________________________Control α4 Na2 -- 825 α4 Na2 1 to 1 1826 α4 Na2 2 to 1 24______________________________________
|Patente citada||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US2996480 *||4 Sep 1959||15 Ago 1961||Dow Chemical Co||Method of inhibiting exothermic reaction in butadiene rubber emulsion polymerizations|
|US3112298 *||4 Feb 1960||26 Nov 1963||Union Carbide Corp||Organoboron polymerization catalysts|
|US3278508 *||14 Ene 1963||11 Oct 1966||Phillips Petroleum Co||Preparation of diene polymers in the presence of an organolithium initiator and a group iib or ivb metal containing adjuvant|
|US3526604 *||1 Sep 1965||1 Sep 1970||Cities Service Co||Polymerization of unsaturated monomers with catalysts formed from the reaction of metals and derivatives of groups i-a and ii-a with compounds of group iii-a|
|US3972863 *||5 Mar 1974||3 Ago 1976||Gennady Nikolaevich Petrov||Method for preparing copolymers from conjugated dienes and monovinylaromatic compounds with random distribution of monomer units|
|US4079176 *||17 Jun 1976||14 Mar 1978||Compagnie Generale Des Etablissements Michelin||Polymerization process|
|Patente citante||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US4866120 *||9 Jun 1988||12 Sep 1989||Mobil Oil Corporation||Elastomeric end difunctional polymers|
|US4977220 *||20 Feb 1990||11 Dic 1990||Hughes Aircraft Company||Epoxy end-capped diolefin derivatives, polymers thereof, and processes for forming same|
|US5063190 *||19 Jun 1990||5 Nov 1991||Gencorp Inc.||Anionic initiator system for polymerizing monomers|
|US5071812 *||30 Jul 1990||10 Dic 1991||Shell Oil Company||Polymerization of cyclic olefins|
|US5147950 *||8 Ago 1991||15 Sep 1992||Shell Oil Company||In-mold polmerization of cyclic olefins with borohydride cocatalyst|
|US5180799 *||21 Dic 1990||19 Ene 1993||Imperial Chemical Industries Plc||Process for polymerizing methacrylic acid ester monomers|
|US5202499 *||8 Ene 1991||13 Abr 1993||Gencorp Inc.||Liquid telechelic polymers having high 1,4-diene structure|
|US5216181 *||26 Ago 1991||1 Jun 1993||Gencorp Inc.||Liquid telechelic polymers having high 1,4-diene structure|
|US5336726 *||11 Mar 1993||9 Ago 1994||Shell Oil Company||Butadiene polymers having terminal silyl groups|
|US5376745 *||1 Dic 1993||27 Dic 1994||Shell Oil Company||Low viscosity terminally functionalized isoprene polymers|
|US5391637 *||23 Nov 1993||21 Feb 1995||Shell Oil Company||Capping of anionic polymers with oxetanes|
|US5418296 *||6 Oct 1994||23 May 1995||Shell Oil Company||Capping of anionic polymers with oxetanes|
|US5461112 *||5 May 1995||24 Oct 1995||Shell Oil Company||Epoxidized monohydroxylated block polymer, epoxy resin, curing agent and epoxy diluent|
|US5576388 *||28 Ago 1995||19 Nov 1996||Shell Oil Company||Telechelic polymers and heterotelechelic polydiene block polymers with dual cure systems|
|US5663250 *||16 May 1996||2 Sep 1997||Shell Oil Company||Deprotection with molten salt|
|US5721316 *||3 Jul 1996||24 Feb 1998||Shell Oil Company||Process for incorporation of expoxidized polydienes into epoxy resins|
|US5721318 *||12 Abr 1996||24 Feb 1998||Shell Oil Company||Pressure sensitive structural adhesives and sealants based on telechelic/heterotelechelic polymers with dual cure systems|
|US5804657 *||16 Ago 1996||8 Sep 1998||Shell Oil Company||Adhesives and sealants based on telechelic polymers and heterotelechelic block polymers with dual cure systems|
|US5880217 *||28 May 1996||9 Mar 1999||Shell Oil Company||Telechelic and heterotelechelic polymers with dual curing agents|
|US5910541 *||18 Sep 1997||8 Jun 1999||Shell Oil Company||Telechelic polymers and heterotelechelic polydiene block polymers with dual cure systems|
|US5910542 *||13 May 1998||8 Jun 1999||Shell Oil Company||Adhesives and sealants based on telechelic polymers and heterotelechelic block polymers with dual cure systems|
|US5948863 *||18 Sep 1997||7 Sep 1999||Shell Oil Company||Telechelic polymers and heterotelechelic polydiene block polymers with dual curing systems|
|US6001469 *||28 Mar 1996||14 Dic 1999||Ppg Industries Ohio, Inc.||Thermosettable primer and topcoat for plastics, a method for applying and coated plastic articles|
|US6075097 *||19 May 1998||13 Jun 2000||Shell Oil Company||Process for producing conjugated diene diols using carbon dioxide|
|US6146706 *||29 Sep 1999||14 Nov 2000||Ppg Industries Ohio, Inc.||Thermosettable primer and topcoat for plastics a method for applying and coated plastic articles|
|US6177603 *||12 Jun 1998||23 Ene 2001||Bridgestone Corporation||Organo zinc and rare earth catalyst system in the polymerization of conjugated dienes|
|US6203913||16 Dic 1998||20 Mar 2001||Ppg Industries Ohio, Inc.||Coating composition for plastic substrates|
|US6242537||2 Mar 1999||5 Jun 2001||Shell Oil Company||Gel-free process for making hydrogenated functionalized anionically polymerized polymers|
|US6242538||4 May 1999||5 Jun 2001||Shell Oil Company||Process for making hydrogenated gel-free functionalized anionically polymerized polymers|
|US6391981||29 Mar 2000||21 May 2002||Kraton Polymers Us Llc||Increased throughput in the manufacture of anionic polymers by reduction in polymer cement viscosity through the addition of metal alkyls|
|US6420490||24 Nov 1999||16 Jul 2002||Kraton Polymers U.S. Llc||Telechelic polymers are produced by ozonation degradation of diene polymers|
|US6455651||14 Mar 2000||24 Sep 2002||Kraton Polymers U.S. Llc||Uniform initiation of anionic polymerization using organo-substituted alkali metal initiators|
|US6462143||20 Ene 1999||8 Oct 2002||Kraton Polymers Us Llc||Gel-free process for making functionalized anionically polymerized polymers|
|US6492466||26 Mar 2002||10 Dic 2002||Kraton Polymers U.S. Llc||Increased throughput in the manufacture of anionic polymers by reduction in polymer cement viscosity through the addition of metal alkyls|
|US6492469||26 Mar 2002||10 Dic 2002||Kraton Polymers U.S. Llc||Increased throughput in the manufacture of anionic polymers by reduction in polymers by reduction in polymer cement viscosity through the addition of metal alkyls|
|US6525142 *||7 Mar 1995||25 Feb 2003||Kraton Polymers U.S. Llc||Monohydroxylated diene polymers and epoxidized derivatives thereof|
|US6593423||3 May 2000||15 Jul 2003||Ppg Industries Ohio, Inc.||Adhesion promoting agent and coating compositions for polymeric substrates|
|US6605680||7 Abr 2000||12 Ago 2003||Eastman Chemical Resins, Inc.||Low color, aromatic modified C5 hydrocarbon resins|
|US6881795 *||28 Mar 2001||19 Abr 2005||Firestone Polymers, Llc||CO2 terminated rubber for plastics|
|US6979714||1 Abr 2003||27 Dic 2005||Ppg Industries Ohio, Inc.||Adhesion promoting agent and coating compositions for polymeric substrates|
|US7009000||11 Jul 2003||7 Mar 2006||Kraton Polymers U.S. Llc||Coupled styrenic block copolymers and process for preparing same|
|US7105613||4 Feb 2005||12 Sep 2006||Firestone Polymers, Llc||CO2 terminated rubber for plastics|
|US7396887 *||29 Dic 2006||8 Jul 2008||Bridgestone Corporation||Insitu removal of chelator from anionic polymerization reactions|
|US7560509||29 Dic 2006||14 Jul 2009||Bridgestone Corporation||Method of directing grafting by controlling the location of high vinyl segments in a polymer|
|US7714069||22 Sep 2006||11 May 2010||E. I. Du Pont De Nemours And Company||Method of producing adherent coatings on resinous substrates|
|US7737218||29 Dic 2006||15 Jun 2010||Bridgestone Corporation||Method for generating free radical capable polymers using tin or silicon halide compounds|
|US7763679||22 Sep 2006||27 Jul 2010||E.I. Du Pont De Nemours And Company||Adherent coating compositions for resinous substrates|
|US8030410||29 Dic 2006||4 Oct 2011||Bridgestone Corporation||Method for generating free radical capable polymers using carbonyl-containing compounds|
|US8227038||11 Ene 2008||24 Jul 2012||E I Du Pont De Nemours And Company||Adhesion promoting cleaner solution|
|US8716409||29 Dic 2006||6 May 2014||Firestone Polymers, Llc||Carboxylate terminated polymers and their use in impact-modified plastics|
|US20020183468 *||28 Mar 2001||5 Dic 2002||Graves Daniel F.||CO2 terminated rubber for plastics|
|US20030212209 *||1 Abr 2003||13 Nov 2003||Kondos Constantine A.||Adhesion promoting agent and coating compositions for polymeric substrates|
|US20040054090 *||11 Jul 2003||18 Mar 2004||Kraton Polymers U.S. Llc||Coupled styrenic block copolymers and process for preparing same|
|US20040171778 *||13 Nov 2002||2 Sep 2004||Donker Chretien Pieter Louis C.||Low color, aromatic modified C5 hydrocaron resins|
|US20040254321 *||29 Jun 2004||16 Dic 2004||Willis Carl Lesley||Uniform initiation of anionic polymerization using organo-substituted alkali metal initiators|
|US20050131153 *||4 Feb 2005||16 Jun 2005||Graves Daniel F.||CO2 terminated rubber for plastics|
|US20070066757 *||22 Sep 2006||22 Mar 2007||Corcoran Patrick H||Method of producing adherent coatings on resinous substrates|
|US20080161448 *||29 Dic 2006||3 Jul 2008||Dedecker Mark N||Carboxylate Terminated Polymers and Their Use in Impact-Modified Plastics|
|US20080161455 *||29 Dic 2006||3 Jul 2008||Hall James E||Insitu removal of chelator from anionic polymerization reactions|
|US20080161484 *||29 Dic 2006||3 Jul 2008||Hall James E||Method of Directing Grafting by Controlling the Location of High Vinyl Segments in a Polymer|
|US20080161495 *||29 Dic 2006||3 Jul 2008||Hall James E||Method for Generating Free Radical Capable Polymers Using Tin or Silicon Halide Compounds|
|US20080161501 *||29 Dic 2006||3 Jul 2008||Hall James E||Method for generating free radical capable polymers using carbonyl-containing compounds|
|US20100021640 *||11 Ene 2008||28 Ene 2010||E. I. Du Pont De Nemours And Company||Adhesion promoting cleaner solution|
|US20100112358 *||22 Sep 2006||6 May 2010||Corcoran Patrick H||Adherent coating compositions for resinous substrates|
|US20110027803 *||17 Dic 2008||3 Feb 2011||Artin Moussavi||Compositions and Methods for Maintenance of Fluid Conducting and Containment Systems|
|EP0697247A2||14 Jul 1995||21 Feb 1996||Shell Internationale Research Maatschappij B.V.||Process for the conversion of hydrocarbonaceous feedstock|
|EP0698638A1||14 Jul 1995||28 Feb 1996||Shell Internationale Research Maatschappij B.V.||Crosslinkable waterborne dispersions of hydroxy functional polydiene polymers and amino resins|
|EP0781605A1||18 Dic 1996||2 Jul 1997||Shell Internationale Research Maatschappij B.V.||Removal of metal compounds from an acid solution|
|EP0781782A1||18 Dic 1996||2 Jul 1997||Shell Internationale Research Maatschappij B.V.||Removal of alkali metal compounds from polymer cements|
|EP0781784A1||18 Dic 1996||2 Jul 1997||Shell Internationale Research Maatschappij B.V.||Removal of an alkali metal compound from a polymer cement|
|WO2009077760A1||17 Dic 2008||25 Jun 2009||Lux Innovate Ltd||Compositions and methods for maintenance of fluid conducting and containment systems|
|Clasificación de EE.UU.||549/513, 526/177, 585/507, 526/335, 564/485, 568/867, 564/14, 568/878, 562/551, 568/857, 568/57, 526/178|
|Clasificación internacional||C08F4/42, C08F4/00, C08F36/04, C08F2/60|
|27 Oct 1983||AS||Assignment|
Owner name: NATIONAL RESEARCH DEVELOPMENT CORPORATION, 101 NEW
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:RICHARDS, DAVID H.;STEWART, MALCOLM J.;REEL/FRAME:004188/0079
Effective date: 19830818
|17 Oct 1988||FPAY||Fee payment|
Year of fee payment: 4
|14 Oct 1992||FPAY||Fee payment|
Year of fee payment: 8
|18 Oct 1996||FPAY||Fee payment|
Year of fee payment: 12